1. Field of the Invention
The present invention relates to a contents delivery system and a contents delivery method for delivering large-capacity contents upon users' requests.
2. Description of the Prior Art
Conventionally, to deliver large-capacity contents such as movies to user terminals, CDN (Contents Delivery Network) has intervened between an archive server storing contents in large quantity and the user terminals because only use of the Internet is insufficient. The CDN is a network in which edge servers serving as relay servers located in respective regions are connected, wherein the edge servers are stored with a large number of contents probably favorite to users. Thereby, by accessing the edge servers without directly accessing the archive server, the users can view favorite contents in a relatively short time in the form of streaming or by downloading them. On the other hand, a technology for automatically delivering contents has been developed. According to the technology, large-capacity storage devices such as hard disk drives are connected to user terminals, and according to contracts with a system administrator, desired contents are automatically delivered directly to the hard disk drives within homes from an archive server through an artificial satellite or the Internet. Therefore, according to such a satellite delivery system, the users can view desired contents at favorite times.
However, in the case of a contents delivery system in which edge servers intervene between an archive server and user terminals, although the edge servers store relatively popular contents, they may not match actual users' preferences, in which case the users may directly access the archive server through the Internet. Repeated occurrence of such a situation would increase the load on the archive server and the Internet, make it difficult to maintain a given service quality, and lose opportunities to provide services for customers, damaging reliability for the system. Also, since the edge servers installed at very high cost are not effectively used, the withdrawal of invested costs may become slow.